Centerless grinding machine



Feb. 7, 1933. R. A. COLE 1,896,481

CENTERLESS GRINDING MACHINE Filed June 27. 1925 4 Sheets-Sheet l WITNESSES I OR MM Bu ymond ll. Cole 1 Q ,9? ,Q, a an a. M T '1 ATT NEY Feb. 7, 1933.

R; A. COLE CENTERLES S GRINDING MACHINE Filed June 27. 1925 4 Sheets-Shee t 2 g; l I a l I H P E IN! I H II g i i i 1' i i z: H lia i i a i l I g .i I I I I I I z i 1 E WITNESSES INVENTOR WM fla g lmond flfi'ole Feb. 7, 1933. R. A. COL-E CENTERLESS GRINDING MACHINE Filed June, 27, 1925 4 Sheets-Sheet 3 INVENTOR gamma/1.601s

rm Q 7 Q1 ATT RNEY Feb. '7, 1933. R A. COLE 1,896,481

CENTERLESS GRINDING MACHINE Filed June 27, 1925 4 Sheets-Sheet 4 WITNESS ES INVENTOR Raymond II. Cole @Wim Patented F ch. 7, 1933 UNITED STATES PATENT OFFICE RAYIOND A. COLE,

OI WORCESTER IASSACHUSETTB, ASBIGNOB, BY IRENE ASSIGIL IENTS, T0 CINCINNATI GRINDEBS INCOBBORATRD, OI CINCINNATI, OHIO, A COB- IOBATION OF OHIO CENTEB LESS GRINDING CHINE Application filed June 27,

This invention relates to grinding machines and particularly to machines of the centerless grinding type adapted for grinding cylindrical or tapered work.

Centerless rinding machines, in general, may be classihed into two types. In one type the work is moved axially during the grinding operation, while in the other type the work does not move axially during grinding. Heretofore, in order to eject work from a machine of the latter type, a separate ejecting operation has been necessary in addition to one or more other operations performed when work is to be removed from the machine. Operation of the work ejecting mechanism requires an objectionable amount of the 0perators time and effort and thus limits the output of work and efliciency of operation of a centerless grinding machine.

An object of the present invention is to avoid the above mentioned difficulties and to provide work ejecting mechanism capable of being operated automatically with a mimmum amount of time and effort on the part of the operator and to increase the production and efficiency of a centerless grinding machine.

Ordinary grinding machines employing centers for holding the work are not adapte for centerless grinding and centerless grinding machines are not adapted for grinding work held on centers. The cost of a centerless grinding machine'and of a grinding machine using centers'is so great and the floor space occupied by these machines is 'so' large that the use of the two machines together in a machine shop is often objectionable or prohibitive.

An object of this invention is to provide a low cost simplified type of machine capable of serving asa centerless grinding machine or of grinding the work on centers.

Another object of the invention is to provide a complete unit capable of being attached to an ordinary cylindrical grinding machine using centers to adapt it for centerless grinding.

A further object is to rovide an improved centerless grinding mac ine capable of efliciently grinding cylindrical or tapered work 1925. Serial No. 40,016.

either with or without a shoulder thereon, the machine having grinding and work regulating wheels and being provided with mechanism for removing one of the wheels from contact with the work and for automatically ejecting the work from a position where the wheel may be brought into contact therewith.

The invention is particularly a plicable to grinding machines of the type isclosed in H. Norton Patent No. 762,838 patented June 14, 1904. This patent describes details of construction of. several parts of the machine hereinafter referred to. In accordance with one phase of the present mvention, a centerless grinding machine having a grinding element and a work regulating element is provided with a work ejecting mechanism arranged to be automatically operated when one of the elements is moved in relation to the other element or the work. When a work piece has been completely ground or when it is desired to remove a work piece from the machine, the grinding wheel is moved away from the regulating wheel by mechanism which automatically operates the ejector.

A handle is provided for rotating a control shaft to movethe grinding wheel to or from the work piece. Mechanism associated with the shaft operates ejecting mechanism which moves the work in an axial direction out of rinding relation with the grinding wheel a or the wheel has moved away from the work to a distance sufficient to permit of free movement of the work relative to the grinding wheel. Mechanism is provided for adjusting the position of the grinding wheel to or from the work, independently of the work ejecting mechanism.

In order to adapt a grinding machine having work holding centers for use as a centerless grinding machine, a complete auxiliary unit is provided for mounting on the machine adjacent the active face of the grinding wheel and preferably on the work carrying table, the machine being cleared of such parts of the original machine as interfere with the use of the centerless grinding unit. When use is made of a machine of the kind disclosed in the Norton patent mentioned ly by reference to the following detailed description in view of the accompanying drawin s, in which:

1gure 1 is an end elevation tion of a portion of a center machine;

Fig. 2 is an enlarged end view of the work ess grinding 3 is a perspective view of the ejector P Fig. 4 is a side elevation of the work regulating wheel unit;

Fig. 5 is a fragmental view of a detail of Fig. 4;

ig. 6 is a side view of the work rest and ejecting mechanism;

Fig. 7 is a front view of mechanism for controlling the feeding movement {of the grind' mgamec ig. 8 mechanism of Fig. 7; g

. Fig. 9 is a side view of a portion of the mechanism for adjusting the position of the work regulating wheel with a part of the frame and mechanism. removed;

. Fig. 10 is an elevation with a portion broken away of the change gear mechanism for controlling the speed of the regulating wheel.

Referring to Fig. 1, the base 10 of the machine supports the grinding wheel 11, mounted on shaft 12 journaled in the shde 13 gulded on ways 14 of the base of the machme. The abrasive work regulating wheel 15 disposed adjacent to the active surface of grindin wheel 11 is mounted on shaft 16 ]0111- nalled in frame 17 supported on the slide table or platen 18, guided on the base 10.

The base of frame 17, resting upon table 18, is fixed in position thereon by the swivel post 19 projecting upward from the table and anism; 1s a cross section on lme 88 of the - fittingwithin recess 20. Table 18 is adjusted on its ways to a position such that the active surface of regulating wheel 15 is disposed opposite the active surface of grinding wheel 11. Ordinarily, the axis of shaft 12 of the grinding wheel is preferably disposed substantially parallel to the direction of, movement of the table 18 on the base 10, as well as parallel to shaft 16. of regulating wheel 15, but may depart from this relationship, if desired. When work is to be ground to a tapered form, frame 17 is adjusted angularly about post 19 so that the active face of the regulating wheel 15 is inclined at the partly in sec wheel and for operating the ejectproper angle to the active face of the grind inclined bearing surfaces 29 and 30, is provided as shown by dotted lines in Fig. 6. Ad-' justing screw 31. may be rotated in one di- \.;rection to advance the wedge toward the right to elevate the work rest 21, or may be rotated in the opposite direction to permit the wedge to recede and to allow the work restto be lowered.

Grinding wheel 11 is moved .towardor away from the regulating wheel'15 and the wor on rest 21 by rotation of feed screw 32 meshing with the depending threaded extension 33 of slide 13. Screw shaft 32 is rotated by spur gear 34 fast thereto and meshmg with pinion 3'5 integral with or fast to spur gear 36. Gear 36 is normally held fast to shaft'37 by pinion 38 and index pin 39 carried by arm 40, fast to'shaft 37. Shaft 37 is journalled in bearings in the hub of gear 36 and pinion 35. Pinion 38 and index pin 39 are provided for fine adjustment of shaft 37 in angular relation with gear 36, this mechanism being described in detail in the Norton patent mentioned above.

Gear 41, fast to shaft 37, meshes with the quadrantspur gear 42 fast to shaft 43. Shaft 43 is rotated by crank 44 having the handle 45 thereon. Casing 46 provides a protective housing for gears 34, 35, 41 and 42. Counter-clockwise rotation of crank 44 may be limited by moving the bolt 47 axially outward, as shown in Fig. 8, to block the rotation, the outward movement of bolt 47 being limited by the end of screw 48 engaging one end of the axial recess 49 in the upper side .of the bolt. Clockwise rotation of crank 44 in moving the grinding wheel toward the work is limited by limiting the rotation of gear 36 by the stop 50 abutting against the free end of pawl 51 pivoted to casing 46. The grinding wheel may, thus be quickly and positively adjusted toward the work to a predeterminedposition fixed by the settingof pinion 38 on the periphery of gearwheel 36.

After truing the regulating wheel 15 or. the

grinding wheel 11 the normal separation between the wheels may be restored by adjusting pinion 38 to a new position on the periphery of gear wheel 36 to compensate 37 for providing a rapid adjustment of feed screw 32 to move rinding wheel 11 rapidly tension by pin 65 ast tothe frame of the machine. Lug 61 limits the rotation of lever 62 in a clockwise rotation. The cam 66 atthe other end of lever 62 engages the follower 67 on'the short arm of lever 68, supported on pivot 69, supported by the base 23 of the work rest. Pin 70 projecting from the long arm of lever 68 slides freely within slot 71 in the short arm of lever 72 supported on pivot 73 on base 23. The u per long arm of lever 72 is bifurcated, the orked end 74 of the lever fitting within the annular recess between shoulders 75 of ejector pin 76 which is longitudinally reciprocatable within the base 23.. Movement of pin 76 to the right is limited by the shoulder ortion 77 of the enlarged end 78 which is ma e comparatively thin to permit wheels 18 and 15 to be brought close together without engaging the end 78. The end 78 is disposed to one side of the workrest 21in a position approximately in axial alignment with the axis of a workpiece supported by rest 21. Rotation of pin 76 on its axis is prevented by the pin 7 9 fast at its upper end to base 23 and having a freely sliding fit at its other end in the axial channel 80, shown in dotted lines, Fig. 6, in the upper side of pin 7 6.

Helical spring 81, fixed at one end to base.

23 and at the other end to pin 82 on the hub of lever 68, urges lever 68 angularly in a counter-clockwise direction, thus ten ing to cause the rotation of lever 72 in a clockwise direction which 'is limited by the limited movement of ejector pin 76.

When handle 45 is turned in a counterclockwise direction the grinding wheel is moved to a predetermined distance away from the work to afford ample space for axial movement of the work without interference with the grinding wheel 11. The cam 66 at the end of tripping lever 62 on shaft 43 then engages the follower 67 on lever 68 and causes a more rapid clockwise rotation of lever 68 than that of shaft 43. Clockwise rotation of lever 68 produces a more rapid counterclockwise rotation of lever 72 which in turn produces a quick ejecting of movement of ejector pin 76 which axially advances the work piece out of operative relation with the wheels 11 and 15 and work rest 21.

The end of cam 66 in the meantime passes by the engaged end of follower 67 so that lever 68 is free to return to its normal condition under the control of spring 81, thereby restoring ejector pin 76 to its normal position. Wheels 11 and 15 are by this time separated far enough to permit of convenient insertion of another work piece.

After insertion of another work piece handle 45 is turned back, that is, in a cloc wise direction. Tripping lever 62 yields by rotating in a counter-clockwise direction relative to pivot 63 when shaft 43 rotates in a clockwise direction. Lever 62 is returned to normal position by spring 64 when it has escaped by follower 67. Handle 45 is thus rotated to the right to move wheel 11 into grinding relation with the work without operating ejector pin 76, and is thus restored to normal position independently of the ejecor. tained by the unequal lengths of the arms of levers 68 and 72 results in a quick ejection of the work piece when the handle 45 is rotated at a moderate velocity.

The motor 83 supported on frame 17 of the regulating wheel unit has the shaft-84 having the pinion 85 fast thereto meshing with gear 86 which is freely rotatable on shaft 87 having pinion 88 fast thereto meshing with gear 89 fast to shaft 90 havin gear 91 fast thereto. Gear 97 is axially sli able on shaft 87, being held angularly fast thereto by loosely splining the shaft to the gear, or by other well known means. The gear shifting knob 93 is fast to pin 94 axially slidable in casing 95, the pin having the forked arm 96 fast thereto and disposed on opposite sides of gear 97 to shift the gear into and out of mesh with gear 91, according as knob 93 is disposed to the right or the left. Pin 94 1s normally urged to the right by helical spring 99, shown in dotted lines, and may be held to the left by turning the pin so that one of the halves 100 of the split collar of the knob is turned into axial alignment with the other half 101 of the collar and prevents movement of the pin to the right, as shown in Fig. 5.

When pin 94 is thrust to the right, as shown in Fig. 4, the arm 96 slides gear 97 to the right, out of engagement with pinion 98, and brings the clutch member 102 on the hub of gear 97 into engagement with the clutch member 103 on the hub of gear 86, thereby lockin%gear 86 to shaft 87.

haft 87 carries the sprocket gear 104 fast thereto. Chain belt 105 meshing with sprocket gear 104 meshes also with sprocket gear 106 fast to shaft 107 having the belt pulley 108, Fig. 4, fast thereto, belted by belt 109 to pulley 110 fast to the shaft 16 of regulating wheel 15.

The ratio of gear train 85, 86, 88, 89, 91, 97 is such that the motor drives the regulating wheel at operating speeds to cooperate with the work rest in controlling the position and The multiplication of movement obof engagement with ear 91, and clutch member 102 enga es wit clutch member 103, so that the reg atin'g wheel is driven through the medium of ears 85 and 86, the gear 86 being locked to s aft 87. The resulting speed is suitable for truing the regulatin wheels, being several times that required or operating the regulating wheel when grinding is taking place.

In order to tighten the chain to the pro r degree, the shaft 107, for the upper sproc et gear, is journalled eccentrically in a cylindrical bearing member 111 which is rotatable toany desired osition where it may be locked b tightening Bolt 112, shown in dotted lines, ig. 1, to clam the split collar 113 tightl in contact with t e bearing member 111. he weighted belt tightener 114, pivoted on shaft 105, provides the necessary tension in belt 109.

' When work is being ground by the machine, the work piece 115 is in contact with the active surfaces of the grinding wheel and the regulating wheel and is supported or guided in position between the active surfaces of wheels 11 and 15 by work rest 21. The work piece rotates at such a speed that its peripheral surface being ground travels at approximately the same velocity as the perlpheral surface of the regulating wheel engaging therewith. When the work has been ground to the desired diameter or when it is desired to remove a work piece from the machine, it is only necessary to turn handle to the left, the work piece bein ejected automatically after the grinding w eel has been moved away from the work a predetermined distance. The work piece may be replaced in operative relation to the grinding and regulatmg wheels, or-.a new work piece may be placed in operative relation to the wheels and the grinding wheel restored to its normal position for grinding the work by rotating handle 45 to the right, or in a clock-- wise direction. Owing to the automatic operation of the ejector mechanism the o ration of the machine is greatly simplifie, and a higher production of work may be obtained from the machine than with prior machines of this type.

. The frame supporting the work regulating wheels and motor drive together with the work rest sup ort and control are readily attachable to t e bed of an ordinary grinding machine employing centers or to the sliding table of a grinding machine such as that dliiclosed in the Norton patent mentioned a ve.

It will thus be seen that a grinding machine employing centers may be readily con-' tively simple low cost unit to the assembly adapted for grinding on centers, and the cost of manufacture and the floor space occupied by the machines are much less than in the case where a separate machine is emplo ed 1 It will be understood that the specific details described above refer merely to an example of one modification of a machine illustrative of the invention disclosed. Features of the invention considered to be novel are set forth in the appended claims.

- I claim:

1. In a eenterless grinding machine, a grinding element, means for controlling the contact of work with saidelement, means for movin said grinding element toward and away mm the work, a handle for controlling said moving means, and means operated by said handle for ejecting work from grinding relation with said grinding element.

2. In a centerless grinding machine, a grinding element, a work re ulating element, means'to position the work in operative contact with said grinding element, means for moving one of said elements toward or away from t e other, means operated by said movin means for ejecting work from grindin re ation with said grinding element, an means whereby said grinding element may be slowly and finely moved relative to the work independently of said work ejecting means.

3. A centerless grinding machine comprising a rapidl rotatable grinding wheel, a slowly rotata le regulating wheel,.a work positioning member to hold a piece of work in operative contact with said wheels, manually operable means for removing the grindin wheel from normal inding position an means operated by sald means and in timed relation therewith for positively moving the for on centers End for center as grin n work axially relative to the grinding zone I when the grinding wheel is away from its normal grinding osition.

4. In a center ess inding machine for work having ashouldia i, a rapidly rotating grinding wheel, a slowly rotating work regulating wheel, means for ositiom'ng and holding'the work between sald wheels and for engaging the shoulder of the work, means for moving the grinding wheel toward and from the work, and means operated by said moving means during movement of the grinding wheel away from thework for ejecting the work from operative relation with said wheels.

5. A centerless grinding machine comprising a rapidly rotating grinding wheel, a slowly rotating regulating wheel peripherally opposed'thereto, the axes of the wheels being parallel, a work support between the wheels, mechanism for moving the grindin wheel into and .out of operative relation wit the work to grind the same to a given size and means operated in timed relation with said mechanism to move the work axially when the grinding wheel is away from its normal grinding position.

6. In a centerless inding machine, a rapidly rotating grin ing wheel, a slowly rotating regulating wheel, means for moving said grinding wheel towards and from the.

ing element in axial alignment with the work and freely slidable in said support axially of the work, a lever arranged to impart sliding movement to said element, a shaft having a cam thereon, a lever for following said cam, and a loose linkage between said levers, said follower lever and linkage being arranged to cause the operation of said ejecting element when said cam rotates in one direction and permitting rotation of said cam in the opposite direction independently of said ejecting element.

8. The combination with a grinding machine having a grinding wheel. and a bed extending in a direction lengthwise past the operative surface of said 'nding wheel and shaped to accommodate t ereon a head stock or a tail stock or both, of means for converting said grinding machine for centerless grinding, said means comprising a frame attachable to and detachable from said bed, a regulating wheel rotatably mounted in said frame for controlling the rotation of a round work piece during grinding action thereon by the grinding wheel, means for adjusting said frame about a substantially vertical axis to permit predetermination of the angular relation between the adjacent operative surfaces of said two wheels. and means for holding work of round section between said wheels.

9. The combinatiorp with a grinding machine having a grinding wheel. and a bed extending in a direction lengthwise past the operative surface of said grinding wheel and shaped to accommodate thereon a head stock or a tail stock or both, of means for converting said grinding machine for centerless grinding, said means comprising a frame attachable to and'detachable from said bed, a regulating wheel rotatably mounted in said frame for controlling the rotation of a round work piece during inding action thereon by the grinding whee means for holding work of round section in operative relation to the adjacent operative surfaces of said two wheels, said grinding machine having means for moving said grinding wheel toward or away from the bed, and means res nsive to operation of said grinding whee movin tending in a direction lengthwise past the.

operative surface of said grinding wheel and shaped to accommodate thereon a head stock or a tail stock or both, of means for converting said grinding machine for centerless grinding and for providing a grinding throat of which said grinding wheel forms one member, said means comprising a frame attachable to and detachable from said bed,

a regulating wheel mounted in said frame and adapted to form another member of the grinding throat and adapted to control the rotation of work of round section during grinding action thereon by said grinding wheel, means for holding work of round section in operative relation to said two wheels and forming another member of the grinding throat, said grinding machine having mechanism for moving said grinding wheel in a direction to enlarge the grinding throat,

means for moving a work piece relative to' said grinding throat, and means detachably connecting said work piece moving means to said mechanism when said frame is attached to ,said bed, for moving a work piece relative to said grinding throat when the latter is enlarged, said lengthwise-extending bed being constructed to receive a head stock or a tail stock for holding and rotating work of round section for operation thereon by said grinding wheel in the absence of said frame and regulating wheel and said frame being constructed to be attachable to or detachable from said bed.

11. The combination with a grinding machine having a grinding wheel, and a bed extending in a direction lengthwisepast the operative surface of said grinding wheel and shaped to accommodate thereon a head stock or a tail stock or both, of means for converting said grinding machine for centerless grindlng and for providing a grinding throat of which said grinding wheel forms one member, said means comprising a frame attachable to and detachable from said bed, a regulating wheel mounted in said frame and adapted to form another member of the grinding throat and adapted to control the rotation of work of round section during grinding action thereon by said grinding wheel, means for holding work of round section in operative relation to said two wheels and forming another member 'of the grinding throat, said grinding machine having means for moving said grinding wheel toward or away from the bed, and a plunger havingba detachable connection with and operated y said grinding wheel moving means for-mow ing a work piece relative to said grinding throat, said lengthwise-extending bed being constructed to receive a head stock or a tail stock for holding and rotating,

work of round section for operation thereon by said grinding wheel in the absence of said frame and regulating wheel and said frame being constructed to be attachable to or detachable from said bed.

12. The combination with a grinding machine having a grinding wheel, and a bed extending in a direction lengthwise past the operative surface of said grinding wheel and shaped to accommodate thereon a head stock or a tail stock or both, of means for converting said grinding machine for centerless grinding and for providing a grinding throat of which said grinding wheel forms one member, said means comprising a frame attachable to and detachable from said bed, a regulating wheel mounted in said frame and adapted to form another member of the grinding throat and adapted to control the rotationof work of round section during grinding action thereon by said grinding wheel, means for holding work of round section in operative relation to said two wheels and forming another member of the grinding throat, mechanism forming part of said grinding machine for moving grinding wheel in a direction to change the rela- -tion of the grinding throat to the work mechanism for moving a work piece relative to said grinding throat, and detachable connections between said two mechanisms whereby one of said mechanisms operates in timed relation to the other, said lengthwise-extending bed being constructed to receive a head stock or a tail stock for holding and rotating work of round section for operation thereon by said grinding wheel in the absence of said frame and regulating wheel and said frame being constructed to be attachable to or detachable from said bed. i

13. The combination with a grinding machine having a grinding wheel, and a bed extendin in a direction len thwise past the o ratlve surface of said grlnding wheel and s aped to accommodate thereon a head stock or a tail stock or both, of means for convertin said grinding machine for centerless grinding, said means comprising a frame attachable to and detachable from said bed, a regulating-wheel rotatably mounted in said frame for controlling the rotation of a round work piece during inding action thereon by said grinding w eel, a work carrier between said two wheels removably supported frame attachab e to and detachable ment-multiplying means for actuating said,

work-movin means in response to actuation of said whee -moving means, said lengthwiseextending bed bein constructed to receive a head stock or a tail stock for holding and rotating work of round section for operation thereon by said grindin wheel in the absence of said frame and regu atin wheel and said frame being constructed to e attachable to or detachable from said bed.

14. The combination with a rinding machine having a grinding whee, and a bed extending in a direction lengthwise past the operative surface of said grinding wheel and shaped to accommodate thereon a head stock or a tail stock or both, of means for convertin said grinding machine for centerless grindin said means com rising a om said bed, a regulating wheel rotatably mounted in said framefor controlling the rotation of a round work piece during inding action thereon by said grindin w eel, a work carrier between said two w eels removabl supported by said bed and provided wit means adapted upon actuation to move a workpiece relative to said carrier, means for moving said grindin wheel toward or away from said bed, an means responsive to actuation of said last-mentioned means for actuating said work-movin means.

15. The combination wit a grinding machine having a grinding whee and a bed extending in a direction lengthwise ast the operative surface of said grinding w eel and shaped to accommodate thereon a head stock or a tail stock or both, of means for convertin said grinding machine for centerless grindin said means com rising a frame attacha le to and detachab e from said bed, a regulating wheel rotatably mounted in said frame for controlling the rotation of around work piece during grinding action thereon by said inding wheel, a work carrier between said two wheels removably supported by said bed and provided with means ada ted upon actuation to move 'a work piece re ative to said carrier, means for moving said rinding wheel toward or away from said Eed, and means detachably connected to said last-mentioned means for actuating said work-moving means.

16. The combination with a grinding maing said grinding machine for centerless grinding, said means including a frame attachable to said bed, a re latln wheel rotatably mounted in said rame or controlling the rotation of a round work piece during grinding action thereon by said grinding wheel, a driving motor carried by said frame and having driving connections with said regulating wheel for driving the latter at a work-rotation-controlling speed, and a work support carried by said frame and mounted on the latter adjacent said regulating wheel so that when said frame with its regulating wheel, driving motor, and work support is attached to said bed, said work support is interposed between said grinding wheel and said regulating wheel.

Signed at Worcester, Massachusetts, this 23rd day of June, 1925. v

RAYMOND A. COLE. 

